Question

Primary oocyte is
A) Haploid
B) Diploid
C) Polyploid
D) None of the above

Answer 1

Hint: In the process of oogenesis, diploid oogonium undergoes mitosis to finally result in a primary oocyte.

Complete Answer:
An oocyte is a female germ cell or the female gametophyte that is involved in the process of reproduction. It is an immature ovum or the egg cell produced within the ovary of the female flower while it undergoes the process of female gametogenesis.

Option a: A haploid cell cannot undergo the reductional division by mitosis. Therefore, this is the incorrect option.

Option b: As primary oocyte is the by-product of a diploid cell undergoing mitosis, the final outcome of this process i.e. primary oocyte is diploid.
- The process of oogenesis takes place inside the outermost layer of the floral ovaries. Just like the sperm production, the process of oogenesis begins within a germ cell known as oogonium.
- Further, this cell undergoes a process of mitosis to increase in its number. This ultimately leads to the generation of more than one to two million cells enclosed within the embryo. This cell which initiates the process of meiosis is known as primary oocyte.
- This primary oocyte later starts the initiation of the first meiotic division; however, arrests its progression in the first prophase itself. During birth, all future eggs exist within the stage of prophase.
- While in adolescence, the anterior pituitary hormone results in the production of a number of follicles within the female ovary thereby finally resulting in the production of primary oocyte.
Therefore, this is the correct option.

Option c: A polyploid cell cannot undergo the reductional division by mitosis. Therefore, this is the incorrect option.

Option d: As one of the options is correct, therefore, this is the incorrect option.

Thus, the correct option is b) Diploid.

Note: Primary oocytes are responsible for initiating the first meiotic division of the cell.